MagFire

Created by [Know Scratcher] • Started on May 29, 2025

A portable magnetic cannon.

May 29th: Learn how to use CAD software.

I found a CAD software called FreeCAD, and I spend some time learning it through a Youtube tutorial video and reading the docs. youtube tutorial

design

Total time spent: 3h

May 30th: Learn how to design a PCB.

Really, like I learn PCB design the first time, and I'm really hoping I could get used to it. So, I watch a tutorial on youtube and on hackpack guide. Using KiCad is actually easier then I thought.

here's a sample uploaded to jlcpcb.com jlc

Overall, it's still pretty fun to try all these thing that I could have never try living in this environment. Hope the project could go off without a hitch.

Total time spent: 2h

June 1st: Do some research

So today I watched a video that kinda make some ideas for me, but the main thing is that it uses a 450v 650uF capacitor, and I definitely have to worry about that cus I don't really work with full circuiting much, so I'm thinking whether the PCB I might design later will burn out of something.

Then I took out my physics book and start turning the pages and noticed that I don't understand any equation at all. physics book

Therefore instead of working with equations (which I might ask for my physics teacher for some help), I ask Gemini for help on impulse circuit and how to charge the capacitor.

Then it gave me this.(which doesn't work) gemini circuit

Well, it sure doesn't work when I open Falstad circuit. So I just try to design my own, and to my surprise, I think I did a great job. circuit

Total time spent: 2h

June 2nd: Draw a draft design for the cannon

So I drew a draft design on my notebook and did some calculation to make sure I won't violate any local laws.

The funny thing is, I forgot to bring the notebook home, so the image will be updated tomorrow. lol

draft

Total time spent: 2h

June 5th: Went to a local store to look up the items

I went to a local electronic store to see if I can find anything that might be on the design, mostly because I need some ideas to continue my design. By the way, I collected some data for the BOM.

the kinda bom like thing

I then found a youtube video that looks super cool after returning, but it uses a inductor boost, which doesn't work at all.

Then I go with my original plan, find a voltage transformer and a capacitor to store the electric energy, then use a coil to make the magnetic force to push the iron ball out.

I found a voltage transformer on a famous online shopping site locally. It's looking super convincing to me so, probably I'll give it a go. Total time spent: 1h

June 7th: Design schematic

So I drew a little schematic-like thing today and it looks like this the kinda schematic-like thing

Well, I think I have to bring a ruler to the electronic store and measure the size of the capacitor

And I also went to a local hardware store to see if I can find some steel ball (well, actually iron ball), and I found some.

Total time spent: 2h

June 12th: Design PCB.

So today I designed the PCB which I think might just work.

PCB which I think might just work

This is the first time I'm designing a PCB, and I've just learn it from youtube tutorials. Well, the craziest part must be that my teacher had been amazed by this project and jumped off the chair multiple times (like literally, about 4 ~ 5 times).

I also drew the model to 3d print.

model to 3d print

I just can't believe I did it in just 5 hr.

Total time spent: 5h

June 20th: finish the design.

I finish designing today and it look something like this

model

and the PCB

pcb

Then I get everything ready and submit. Total time spent: 2h